August, 2016 - SUPPORT Summary of a systematic review | print this article |

What are the benefits and harms of direct to consumer advertising?

Direct to consumer advertising is increasingly used by the pharmaceutical industry and its merits have been extensively debated. Regulations related to such advertising vary: in New Zealand and the United States of America (USA), for example, regulations do not explicitly prohibit such advertising and its use has grown. In other countries, however, the practice has been banned and heavy lobbying by the pharmaceutical industry has been resisted.

 

Key messages

  • Direct to consumer advertising increases patient demand for advertised medicines and the number of related prescriptions by doctors.
  • The effects of direct to consumer advertising on health out-comes are uncertain.
  • In light of the lack of evidence of the benefits, potential harms, and costs of direct to consumer advertising.

- The value of policies that allow for the increased use of direct to consumer advertising is uncertain at best; and

- Rigorous monitoring and evaluation are warranted when such policies are implemented.

 

Background

The promotion of prescription-only medicines using direct to consumer advertising is used increasingly by the pharmaceutical industry. Proponents of direct to consumer advertising argue that it increases the use of effective treatments for under-treated conditions. Opponents, however, suggest that it drives up demand for newer, higher-cost drugs that may have marginal benefits and unknown safety profiles.



About the systematic review underlying this summary

Review Objectives: To examine the benefits and harms of direct to consumer advertising of prescription-only medicines

Types of What the review authors searched for What the review authors found

Interventions

Randomised controlled trials, controlled clinical trials, controlled before-and-after studies, interrupted time series analyses, and cross-sectional studies with a control group.

3 interrupted time series analyses, 1 comparative cross sectional survey.

Participants

Not pre-specified.

Patients and physicians in primary care (4 studies).

Settings

Not pre-specified.

USA (2 studies), USA and Canada (1), Netherlands (1).

Outcomes

Health seeking behaviours of patients at the point of access to care; requests for prescription only medicines; patient-doctor communication and satisfaction with care; prescribing patterns; costs.

Requests for prescription only medicines (4 studies); prescription volume (4 studies); patient-doctor communication and satisfaction with care (1 study).

Date of most recent search: October 2004.

Limitations: A good quality systematic review with only minor limitations.

Gilbody S, Wilson P, Watt I. Benefits and harms of direct to consumer advertising: a systematic review. Qual Saf Health Care 2005;14:246-50. See in PubMed

Summary of findings

The review included 4 studies that compared the impact of direct to consumer advertising. Of these, 2 were conducted in the USA, 1 in the USA and Canada and 1 in the Netherlands.

A synthesis of the four studies showed that:

  • Direct to consumer advertising increases patient requests and prescription volume for advertised drugs. The certainty of this evidence is high.
  • No studies were found that evaluated the impact of direct to consumer advertising on health outcomes or the cost effectiveness of such advertising.

Direct to consumer advertising

People: Patients and clinicians
Settings
: Primary care in USA (2), USA and Canada (1), and Netherlands (1)
Intervention
: Direct to consumer advertising
Comparison
: No intervention
Outcomes Impact Quality of the evidence
(GRADE)
Prescriptions

Prescriptions

DTCA was consistently associated with increased numbers of patient requests and/or increased prescription volume for the advertised medicines.

High

Health outcomes

No studies examined the impact of DTCA on patient satis-faction with care, or the impact of DTCA and altered pre-scribing on actual health outcomes.

-

Costs

No studies examined the cost effectiveness of DTCA by combining health outcomes, or the economic costs of al-tered prescribing.

-

GRADE: GRADE Working Group grades of evidence (see above and last page).
DTCA: Direct to consumer advertising.
[?]: The study in the Netherlands had a total 470,775 patients and 1.5 million patient years, the first study in the USA analysed 195,577 clinician encounters and the second one studied four representative geographical areas but did not give the total number of participants of physician encounters, and the study that compared the USA to Canada recruited 1431 patients and 78 physicians.

Relevance of the review for low-income countries

Findings Interpretation*
APPLICABILITY
  • The studies, all conducted in high-income countries, show that direct to consumer advertising alters prescribing behaviour and volume; but no studies examined the impact of such advertising on health outcomes.
  • Given the absence of any evidence of improvement in health outcomes from direct to consumer advertising, its benefits are uncertain in any settting.
EQUITY
  • None of the studies provided data on the differential effects of direct to consumer advertising
  • The forms of mass media used by pharmaceutical companies may not be available or appropriate for reaching low-income households.
  • However, disadvantaged persons who have access to such mass media may easily be misinformed (due to their relatively lower educational attainment). This may lead to high demand for newer, expensive drugs with unknown safety profiles, and exacerbate existing inequalities.
ECONOMIC CONSIDERATIONS
  • None of the studies examined the cost effectiveness of direct to consumer advertising, or the economic costs of altered prescribing.
  • Any further studies of direct to consumer advertising should evaluate its costs and health and social consequences.
MONITORING & EVALUATION
  • Direct to consumer advertising has not been subject to extensive and rigorous evaluation, even in high-income countries.
  • Rigorous studies of direct to consumer advertising (with an appropriate control) are needed.
  • In the absence of such new evidence, the implementation of direct to consumer advertising in any setting should be closely monitored and evaluated.

*Judgements made by the authors of this summary, not necessarily those of the review authors, based on the findings of the review and consultation with researchers and policymakers in low- and middle-income countries. For additional details about how these judgements were made see: http://www.supportsummaries.org/methods

Additional information

Related literature
1. Frosch DL, Grande D, Tarn DM, Kravitz RL. A decade of controversy: bal-ancing policy with evidence in the regulation of prescription drug advertising. Am J Public Health 2010;100:24-32.
2. Mintzes B, Morgan S, Wright JM. Twelve years' experience with direct-to-consumer advertising of prescription drugs in Canada: a cautionary tale. PLoS One 2009;4(5):e5699.
3. Atherly A, Rubin PH. The cost-effectiveness of direct-to-consumer advertising for prescription drugs. Med Care Res Rev 2009;66:639-57.
4. Norey E, Simone TM, Mousa SA. The impact of direct-to-consumer adver-tised drugs on drug sales in the US and New Zealand. Appl Health Econ Health Policy 2008;6:93-102.
5. Law MR, Majumdar SR, Soumerai SB. Effect of illicit direct to consumer advertising on use of etanercept, mometasone, and tegaserod in Canada: controlled longitudinal study. BMJ 2008;337:a1055.
6. Hoffman JR, Wilkes M. Direct to consumer advertising of prescription drugs.BMJ 1999;318:1301–2
7. Mintzes B. Direct-to-consumer advertising of prescription drugs in Canada. What are the public health implications? Health Council of Canada. January 2006. 
This summary was prepared by 
Charles Shey Wiysonge, School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
Conflict of interest
None. For details, see: www.support-collaboration.org/summaries/coi.htm
Acknowledgements
This summary has been peer reviewed by: Simon Gilbody, UK; Joel Lexchin, Canada
This summary should be cited as
Wiysonge CS. What are the benefits and harms of direct to consumer advertis-ing? A SUPPORT Summary of a systematic review. December 2010. www.support-collaboration.org/summaries.htm
Keywords

Related literature

Frosch DL, Grande D, Tarn DM, Kravitz RL. A decade of controversy: bal-ancing policy with evidence in the regulation of prescription drug advertising. Am J Public Health 2010;100:24-32.

 

Mintzes B, Morgan S, Wright JM. Twelve years' experience with direct-to-consumer advertising of prescription drugs in Canada: a cautionary tale. PLoS One 2009;4(5):e5699.

 

Atherly A, Rubin PH. The cost-effectiveness of direct-to-consumer advertising for prescription drugs. Med Care Res Rev 2009;66:639-57.

 

Norey E, Simone TM, Mousa SA. The impact of direct-to-consumer adver-tised drugs on drug sales in the US and New Zealand. Appl Health Econ Health Policy 2008;6:93-102.

 

Law MR, Majumdar SR, Soumerai SB. Effect of illicit direct to consumer advertising on use of etanercept, mometasone, and tegaserod in Canada: controlled longitudinal study. BMJ 2008;337:a1055.

 

Hoffman JR, Wilkes M. Direct to consumer advertising of prescription drugs.BMJ 1999;318:1301–2.

 

Mintzes B. Direct-to-consumer advertising of prescription drugs in Canada. What are the public health implications? Health Council of Canada. January 2006.

 

This summary was prepared by

Charles Shey Wiysonge, School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa.

 

Conflict of interest

None. For details, see: www.supportsummaries.org/coi

 

Acknowledgements

This summary has been peer reviewed by: Simon Gilbody, UK; Joel Lexchin, Canada.

 

This review should be cited as

Gilbody S, Wilson P, Watt I. Benefits and harms of direct to consumer advertising: a systematic review. Qual Saf Health Care 2005;14:246-50.

 

This summary should be cited as

Wiysonge CS. What are the benefits and harms of direct to consumer advertis-ing? A SUPPORT Summary of a systematic review. December 2010. www.supportsummaries.org

 

Keywords

evidence-informed health policy, evidence-based, systematic review, health systems research, health care, low and middle-income countries, developing countries, primary healthcare, direct to consumer advertising.

 

This summary was prepared with additional support from:

The University of Cape Town (UCT), South Africa. UCT aspires to become a premier aca-demic meeting point between South Africa, the rest of Africa, and the world. Taking advantage of expanding global networks and our distinct vantage point in Africa, we are committed, through innovative research and scholarship, to grapple with the key issues of our natural and social worlds.
www.uct.ac.za



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